Canon Kabushiki Kaisha

Fumiteru Gomi

Yoshiyuki Komiya

Kouichi Hashimoto

Atsushi Takeda

Koichi Hashimoto

Masami Hano

Kenichi Shibuya

Shuichi Kadota

Yoshiaki Kobayashi

Ryuta Ai

Yoichi Kimura

Satoru Fukushima

Makoto Ohki

Keishi Ohsawa

Shigeru Matsuzaki

Kuoichi Hashimoto

A management apparatus that enhances efficiency of maintenance work of a plurality of image forming apparatuses. An apparatus management server is connected to a plurality of image forming apparatuses via a network. Each image forming apparatus includes a storage unit for storing information indicative of wear levels of members for outputting a color image, on a color-by-color basis. The management service acquires the information from each image forming apparatus, and selects an image forming apparatus for outputting an image based on the acquired information such that differences between the wear levels of the members become smaller between the image forming apparatuses.

Management apparatus that manages a plurality of image forming apparatuses, management system, and method of controlling management apparatus

An image forming apparatus includes a member (drum), a charging device, an exposure device, a developing device, a transfer device, a cleaning blade, a selecting device for selecting an execution mode from an image forming mode and a recovery mode, and a controller for controlling a peak-to-peak voltage applied to the charging device in the operation in the recovery mode. When the recovery mode is selected, the controller effects control so that a band-like toner image is formed on the drum and is supplied to the cleaning blade and so that a peak-to-peak voltage of the AC voltage larger than that of the AC voltage applied to the charging device in the operation in the image forming mode is applied to the charging device in a predetermined period after a leading end of the band-like toner image subjected to removal by the cleaning blade passes through the charging device.

Image forming apparatus

An image forming apparatus includes a photosensitive member; a charging device for electrically charging the photosensitive member; an exposure device for exposing to light the photosensitive member electrically charged by the charging device to form an electrostatic image; a developing device for developing the electrostatic image with toner to form a first patch and a second patch; a detecting device for detecting a density of the first and second patches formed by the developing device; and a control device for controlling an image forming condition on the basis of a difference in density between the first patch formed on the photosensitive member at a portion where a surface potential of the photosensitive member is zero volts and the second patch formed at a portion electrically charged by applying a predetermined charging bias to the charging device.

Image forming apparatus with image forming condition control feature based on difference in patch densities

An image forming apparatus includes image bearing member having a movable surface; charging means for charging the surface of the image bearing member; image exposure means for exposing the surface of the image bearing member charged by the charging means to light in accordance with image information, thus forming an electrostatic image; developing means for developing the electrostatic image formed on the image bearing member into a developed image; surface potential detecting means for detecting a potential of the surface of the image bearing member; discharging means for discharging the surface of the image bearing member; changing means for changing an image forming condition, wherein an area of the image bearing member passes the discharging means under different operating conditions of the discharging means, and the area is charged by the charging means, the changing means changes the image forming condition on the basis of a result of detection, by the surface potential detecting means, of surface potentials of the area charged by the charging means.

In an early-middle stage of a photosensitive drum life cycle, an image forming apparatus uses only a second semiconductor laser having an oscillation wavelength 660 nm to perform writing of an electrostatic latent image on a photosensitive drum surface. In a middle-late stage of the photosensitive drum life cycle, the image forming apparatus starts using a first semiconductor laser having an oscillation wavelength of 440 nm in addition to the second semiconductor laser to perform writing of an electrostatic latent image on the photosensitive drum surface with a combined exposure spot formed at the same position. An exposure control unit gradually increases an output rate of the first semiconductor laser according to an increase in total output of the first and second semiconductor lasers.

Image forming apparatus having a exposure control unit capable of changing an exposure ratio between a first exposure ratio and a second exposure ratio different from the first exposure ratio when a first exposure unit or second exposure unit exposes an image carrier on the basis of image data for forming an image with a certain density

An image forming apparatus including an image bearing member, a charging unit for charging the image bearing member, and an image exposure unit including a light emitting portion for emitting light to form an electrostatic image. The image forming apparatus also includes a developing unit including a toner carrying member and a bias controlling unit for applying a bias voltage to the toner carrying member, the developing unit being effective to develop the electrostatic image with toner by a potential difference between the toner carrying member and the electrostatic image, a potential difference determining unit, and a storing unit for storing a light amount control value, corresponding to the potential difference, set on a basis of a light emission amount information inherent to the light emitting portion. The image exposure unit reads the light amount control value and controls the light amount based on the light amount control value.

Image forming apparatus with an image exposure unit light emission control feature

An image forming apparatus having a heating device that is configured to heat an image bearing member so that the detection of the surface potential of the image bearing member can be controlled with greater stability. The image forming apparatus utilizes a surface potential detector and a temperature detecting member placed in positions at a precise distance relative to an exposure portion of the image bearing member, such that the stability of the surface potential detection can be improved. When a surface potential of the image bearing member is detected, it is possible to reduce the amount of change in the potential caused by carriers generated immediately after an exposure operation, and to reduce variations in detection of the surface potential caused by variations in the temperature, so that the surface potential can be controlled with greater stability.

Image forming apparatus with surface potential detection

An electrophotographic image forming apparatus in which a reduction in image density when continuous sheet supply endurance is effected under a low-humidity environment is prevented, and under a high-humidity environment, an image deletion is prevented. A photosensitive member has an undercoat layer, a charge generating layer and a charge transport layer, and the surface layer of the photosensitive member contains a compound of which at least one polymerization functional group has been polymerized or cross-linked and hardened. Also, the hardening of the surface layer is effected by electron irradiation. A temperature raising apparatus for heating the surface of the photosensitive member is controlled by a controlling device to thereby control the surface temperature of the photosensitive member. The controlling device has two or more stages of set temperatures, and uses a high set temperature when the photosensitive member is used under an environment in which the absolute amount of water vapor is great.

Electrophotographic image forming apparatus

A high-precision image control method that can be conducted frequently without time or labor. When a sheet-passing operation starts, maximum exposure is performed at present settings in a predetermined non-image forming area and potential is detected by a potential sensor. Detected potential is compared with Vat a first control to judge whether a difference of 10 V or more exists. For a difference of 10 V or more, the signal is made responsive to laser output for achieving Vset at the first control. When the last image forming for that job is performed, potential returns to the potential set at the first control, and control ends. When the last image forming is completed in a consecutive job during short-term variability of V, Vis restored to its original potential before the next job, whereby settings obtained with the first control are restored.

Image forming apparatus which can clean auxiliary member erasing image traces

An image forming apparatus includes a plurality of image bearing members and a plurality of image forming devices for forming toner images on the respective image bearing members, wherein the toner images formed on the respective image bearing members by the respective image forming devices are successively transferred to a transfer medium, and wherein a toner image for identifying the apparatus is formed on the image bearing member having the highest temperature among the plurality of image bearing members.

Image forming apparatus featuring a temperature-sensitive apparatus identifying feature

An image forming apparatus includes an image bearing member which is movable; an electrifying device which makes contact with the image bearing member and electrifies the image bearing member; a developing device for developing a latent image on the image bearing member by toner; and an abutting member which is provided on a downstream side in a moving direction of the image bearing member with respect to the electrifying device and the contacting portion of the image bearing member and abuts against the image bearing member. The image bearing member, electrified by the electrifying device, is exposed to have the latent image formed thereon, a toner image formed on the image bearing member by the developing device is transferred to a recording material, and the developing device recovers residual toner on the image bearing member after transfer.

Image forming apparatus having a member for barring an electrification particle form leaking

Toner particles fly off from a photosensitive drum to an exposure light emitting portion by a change of electric potential distribution on the photosensitive drum caused by image exposure in a following process. This causes a poor copy of an image by adhering the toner particles to the exposure light emitting portion. This phenomena affects a tandem type of copiers with multi-stations including photosensitive drums and exposure light emitting positions. An apparatus capable of suppressing toner adhesion to an exposure is provided to solve the above problem.

Image forming apparatus with conductive member adjoining light irradiating portion

When image forming is repeated with cleanerless image forming apparatus, &ldquo;positive ghost&rdquo;, which means that a preceding image is slightly left, occurs because a residual toner is not recovered by a developer. Even if an image forming apparatus with an electrically conductive brush or auxiliary device repeats image forming or continuously forms an image with a high image ratio, resistance of the brush increases because the residual toner is deposited on the electrically conductive brush. As a result, advantages of the electrically conductive brush which erases traces of the preceding image are lost. Therefore, in accordance with this invention there are provided an image forming apparatus which does not let image traces leave, and an image forming apparatus which prevents (or reduces) the resistance of auxiliary devices and cleans auxiliary devices.

Growing community of inventors

Abiko, Japan

Fumiteru Gomi